<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html lang="en-us" xml:lang="en-us"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta name="security" content="public" /> <meta name="Robots" content="index,follow" /> <meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' /> <meta name="DC.Type" content="concept" /> <meta name="DC.Title" content="Special considerations for journal entries" /> <meta name="abstract" content="Many journaled integrated file system operations internally use commitment control to form a single transaction from the multiple functions performed during the operations." /> <meta name="description" content="Many journaled integrated file system operations internally use commitment control to form a single transaction from the multiple functions performed during the operations." /> <meta name="DC.Relation" scheme="URI" content="rzaaxjournaloverview.htm" /> <meta name="DC.Relation" scheme="URI" content="../rzaki/rzakifinder.htm" /> <meta name="copyright" content="(C) Copyright IBM Corporation 1999, 2006" /> <meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1999, 2006" /> <meta name="DC.Format" content="XHTML" /> <meta name="DC.Identifier" content="rzaaxspecial" /> <meta name="DC.Language" content="en-us" /> <!-- All rights reserved. Licensed Materials Property of IBM --> <!-- US Government Users Restricted Rights --> <!-- Use, duplication or disclosure restricted by --> <!-- GSA ADP Schedule Contract with IBM Corp. --> <link rel="stylesheet" type="text/css" href="./ibmdita.css" /> <link rel="stylesheet" type="text/css" href="./ic.css" /> <title>Special considerations for journal entries</title> </head> <body id="rzaaxspecial"><a name="rzaaxspecial"><!-- --></a> <!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script> <h1 class="topictitle1">Special considerations for journal entries</h1> <div><p>Many journaled integrated file system operations internally use commitment control to form a single transaction from the multiple functions performed during the operations.</p> <p>These journaled operations should not be considered complete unless the commitment control cycle has a Commit journal entry (Journal Code C, Type CM). Journaled operations that contain a Rollback journal entry (Journal Code C, Type RB) in the commitment control cycle are failed operations, and the journal entries within them should not be replayed or replicated.</p> <p>Journaled integrated file system entries (Journal Code B) that use commitment control in this manner include:</p> <ul><li>AA — Change Audit Value</li> <li>B0 — Begin Create</li> <li>B1 — Create Summary</li> <li>B2 — Add link</li> <li>B3 — Rename/Move</li> <li>B4 — Unlink (Parent Directory)</li> <li>B5 — Unlink (Link)</li> <li><img src="./delta.gif" alt="Start of change" />B7 — Created object authority information<img src="./deltaend.gif" alt="End of change" /></li> <li>FA — Attribute Change</li> <li>JT — Start Journal (only when journaling is started because of an operation in a directory with the inherit journaling attribute of Yes)</li> <li>OA — Authority Change</li> <li>OG — Object Primary Group Change</li> <li>OO — Object Owner Change</li> </ul> <p>Several integrated file system journal entries have a specific data field indicating whether the entry is a summary entry. Operations that send summary entry types will send two of the same entry types to the journal. The first entry contains a subset of the entry specific data. The second entry contains complete entry specific data and will indicate that it is a summary entry. Programs that are replicating the object or replaying the operation will generally only be interested in the summary entries.</p> <p>For a create operation in a journaled directory, the B1 journal entry (Create Summary) is considered the summary entry.</p> <p>Some journaled operations need to send a journal entry that is conversely related to the operation. For example, a commitment control cycle containing a B4 journal entry (Unlink) may also contain a B2 journal entry (Add Link). This type of scenario will only occur in operations that result in a Rollback journal entry (C — RB) .</p> <p>This scenario may occur for two reasons:</p> <ol><li>The operation was about to fail, and the entry was needed internally for error path cleanup.</li> <li>The operation was interrupted by a system outage, and during the subsequent IPL, recovery that needed to send the entry was performed to rollback the interrupted operation.</li> </ol> </div> <div> <div class="familylinks"> <div class="parentlink"><strong>Parent topic:</strong> <a href="rzaaxjournaloverview.htm" title="These topics introduce journaling support for integrated file system objects.">Journaling overview</a></div> </div> <div class="relinfo"><strong>Related information</strong><br /> <div><a href="../rzaki/rzakifinder.htm">Journal entry information finder</a></div> </div> </div> </body> </html>